1. Field of the Invention
The present invention relates to an adjustment assembly, and more particularly to a toe adjustment assembly for adjusting toe-in and toe-out values of an automotive vehicle.
2. Description of the Prior Art
In general, a vehicle is a device being driven at a high speed as well as at a desired direction by steering front wheels. A wheel alignment of the front wheels is closely related to safety and steering performances, specifically to straight driving.
The wheel alignment has a function of properly adjusting camber, toe-in, inclination of king-pin, caster, etc., to meet the performances of a vehicle. The camber and the toe-in provide an essential influence on driving quality of a vehicle. The camber prevents a lower part of a tire from being widened by weight of a vehicle and reduces the adjusting capacity of a steering wheel. On the other hand, the toe-in stops a front side of a tire from being twisted to thereby improve the straight drive. The toe-in inwardly inclines the front side of the tire at a certain angle .theta. as illustrated in a plane of a vehicle in FIG. 5, and plays a role to refrain the front side of the tire (T) from being twisted by the camber while driving, thus improving straight driving stability.
The toe-in is controlled, as shown in FIG. 6, by the length of an arm(55) on the vehicle suspension system which comprises a knuckle(51) linked into a hub(50), a straight assembly(52) perpendicularly connected into the knuckle(51), and the arm(55) aligned between the knuckle for a slanted rotation at one end and bolts(54) of the cross member(53) for rotation at the other end.
In order to control the length of the arm(55), the arm(55) is divided into two, a first arm(55') with a left screw (56) and a second arm(55") with a right screw respectively, and a controlling member (58) is mounted for round traveling of two screws(56 and 57). When the controlling member(58) connected to the screws(56, 57) rotates clockwise or counterclockwise, the arms(55' and 55") and the knuckle(51) are subsequently pulled or expanded to adjust a toe-in. Of course, when adjusting the toe-in, the arm(55) should be separately adjusted since arms are installed at both sides of the suspension system.